None of the terrorists this season have been shown to be praying or praising Allah or performing any other overt religious acts. It does not seem that they are "true believers" but just ideologues. We'll see if the depiction changes. Their religion has not been explicitly mentioned either, although it is apparent that they are from the Near/Middle East. Perhaps the true Muslim is the one working for the Islamic American Alliance, but he hasn't been shown praying either.